(1)Field of the Invention
The present invention relates to a plating apparatus for processing a plurality of block-like works such as calipers or brackets of disk brakes or other parts for automobiles as one works, group, and particularly to the plating apparatus of a plating liquid injection type in which plating liquid is injected to the works by a plurality of plating liquid injection nozzles while electroplating is being performed.
(2)Description of the Prior Art
Japanese patent application No. 58-31478 (first laid-open publication No. 59-157300) commonly assigned to, has disclosed an example of a plating apparatus for processing plate-like works. In this apparatus, a plurality of plating liquid injection nozzles are disposed at opposite sides of one plate-like work suspended in a plating bath, so that the plating liquid is injected onto the work during the plating operation.
In this apparatus and other conventional apparatus, the plating liquid is supplied to the injection nozzles by a pump from a storage tank disposed under the plating bath, so that the liquid injected into the plating bath flows down to the storage tank. The Japanese patent application No. 58-40190 (first laid-open publication No. 59-166697) commonly assigned with this application has disclosed an example of a structure including a storage tank independent of a plating bath.
The present inventor has tried to utilize the plating apparatus of the liquid injection type, which has been utilized only for the plating of the plate-like works, for plating a plurality of block-like works, such as calipers or brackets of disk brakes or other parts for automobiles.
However, the following problems have been found when the conventional apparatus is used without improvement for the plating of the block-like works.
In the plating of a plurality of the block-like works, it is desirable to change or adjust the direction of the injected liquid in order to reduce the processing time and to improve the quality. However, in conventional structures, it is impossible to individually adjust the direction of each injection nozzle.
Further, in the plating of automobile parts, it is necessary to use a plating liquid having strong tendency to foam or bubble so as to reduce the processing time and to improve the quality.
However, in the conventional apparatus, when the process stops after each operation, the plating liquid in the plating tank flows down into the storage tank, and the plating tank becomes empty until the next operation starts. It is therefore necessary to fill to the plating tank by supplying plating liquid, by means of the pump through the nozzles prior to the next operation. This injection of the plating liquid, having a strong tendency to foam into the empty plating tank causes, the entire bath to foam, so that the actual plating operation can not be started until the foam dissipates.